slide-toggle fires undesired event when setting a default value

[fernandobandeira]

Bug

Currently if you set a default value for a slide-toggle it'll emit a ngModelChange event when the view inits, IMO the correct behavior would be to not emit this event since there was no change at all.

What are the steps to reproduce?

http://plnkr.co/edit/imQpobzGdi3Xl6IbXYo7?p=preview

Or use the component below:

import { Component } from '@angular/core';

@Component({
  selector: 'demo-app',
  template: `
    <md-slide-toggle [(ngModel)]="test" (ngModelChange)="change()"></md-slide-toggle>
    <hr>
    <div [hidden] = "hide_msg">
        Change event was received:
    </div>
  `
})
export class AppComponent {
  hide_msg: boolean = true;
  test = true;
  
  change() {
    this.hide_msg = false;
  }
}

Which versions of Angular, Material, OS, browsers are affected?

All browsers and Angular versions...

Even changing test to 1 the event will also be fired...

[devversion]

Thanks for the issue. I will look into it tomorrow.